Ethanol in gasoline & its effects on collector cars ...
I've searched the Forums extensively today, using "W126", "Ethanol", "Fuel" & found only a thread from 2008. The link below/attached is from Hemmings TODAY, & I suggest WE begin to prepare for the inevitable. I'm starting to gather Any & All info today, for use WHEN I've gathered sufficient tech to CONVERT my '88 560SEL BEFORE Mandated (Higher Ratio Blend) Fuels hit me from the Blindside.
We have the mandatory E-10 Blend here in Colorado during part of the year & I NEVER Stray from from 91 Octane Premium, but longevity is paramount with me; 318,000 miles & counting ... IF ANYONE has the OFFICIAL Benz-AG (Germany) info on this, please advise by reply to this post so everyone can be on the same page. Tech 101: Ethanol in gasoline and its effects on collector cars | Hemmings Blog: Classic and collectible cars and parts

If you look in the owners manual (or a supplement that came with the car, I forget which) you'll notice that in the list of acceptable fuels, it states that 10% 'gasohol' is ok. Gasohol was as term used to describe ethanol blended gasoline years ago.

So technically, MB says it's ok to use it.

I try to avoid it, just on principal. I want as close to 100% gasoline in my car as possible. There is a measurable negative change in fuel economy when using ethanol blended fuel.

The other thing is, alcohol absorbs water (that's what dry gas is) and water is the enemy of any fuel system.

Also, when sitting, the alcohol/water mixture will sink to the bottom of the tank. So if you have a car that you seldom drive, and it has a mixture of nasty stuff in it, it'll tend to sink to the bottom of the tank, which is where the fuel is picked up... not really good.

Think about it.. if it's a 10% blend, that would amount to 2 gallons of alcohol in 20 gallons of fuel.

If you look in the owners manual (or a supplement that came with the car, I forget which) you'll notice that in the list of acceptable fuels, it states that 10% 'gasohol' is ok. Gasohol was as term used to describe ethanol blended gasoline years ago.

So technically, MB says it's ok to use it.

I try to avoid it, just on principal. I want as close to 100% gasoline in my car as possible. There is a measurable negative change in fuel economy when using ethanol blended fuel.

The other thing is, alcohol absorbs water (that's what dry gas is) and water is the enemy of any fuel system.

Also, when sitting, the alcohol/water mixture will sink to the bottom of the tank. So if you have a car that you seldom drive, and it has a mixture of nasty stuff in it, it'll tend to sink to the bottom of the tank, which is where the fuel is picked up... not really good.

Think about it.. if it's a 10% blend, that would amount to 2 gallons of alcohol in 20 gallons of fuel.

Yeah, not thrilled about those figures. Unfortunately, the higher-ups (and eco-weenies) in this country assume everyone can buy a new car that'll work with whatever percentage they throw at us next. I personally think E0 gasoline (or just gas-o-frickin'-line) should be available for purchase from all gas stations, but it's not economically feasible for gas stations to have that many tanks. Ridiculous.

We in the UK have a number of neutralising additives on the market now.
There has been a campaign by the FBHVC FBHVC due to the problems it causes older vehicles.
One of which is a US product made by Lucas Oil products (Product not problem)

When Finland moved to mandatory 10% ethanol blended 95 octane Mercedes-Benz released info that all cars older than 1990 were incompatible. This is still their position.

We still get 5% blended 98 octane but no consumer automotive 0% blends.

Since I live on the border, I go to Russia for fuel, where gasoline is still the "real deal" with no additives, ethanol or other capitalist crap. I've measured about 5-10 % better fuel mileage compared to European fuel and I get it for 0.85 e/ltr as opposed to 1.6 e/ltr to boot.